1348:. However, growth in arabinose is regulated by a feedforward loop with an AND gate which confers an approximately 20 minute time delay between the ON-step in which cAMP concentration increases when glucose is consumed and when arabinose transporters are expressed. There is no time delay with the OFF signal which occurs when glucose is present. This prevents the cell from shifting to growth on arabinose based on short term fluctuations in glucose availability.
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with time). Sometimes pure feed-forward control without feedback is called 'ballistic', because once a control signal has been sent, it cannot be further adjusted; any corrective adjustment must be by way of a new control signal. In contrast, 'cruise control' adjusts the output in response to the load that it encounters, by a feedback mechanism.
234:. Feedforward is not typically hyphenated in scholarly publications. Meckl and Seering of MIT and Book and Dickerson of Georgia Tech began the development of the concepts of Feedforward Control in the mid-1970s. The discipline of Feedforward Controls was well defined in many scholarly papers, articles and books by the late 1980s.
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system for execution do not satisfy the above definition of feedforward control. Unless the system includes a means to detect a disturbance or receive an input and process that input through the mathematical model to determine the required modification to the control action, it is not true feedforward control.
127:
difficulty with feed-forward control is that the effects of the disturbances on the system must be accurately predicted, and there must not be any unmeasured disturbances. For instance, if a window was opened that was not being measured, the feed-forward-controlled thermostat might let the house cool down.
401:
are directed and signed, as they represent activation (+) or repression (-). The sign of a path in a transcription network can be obtained by multiplying the signs of the edges in the path, so a path with an odd number of negative signs is negative. There are eight possible three-node FFLs as each of
250:
by the feedforward control system and its driver is typically substantially lower than with other controls. Stability is enhanced such that the controlled device can be built of lower cost, lighter weight, springier materials while still being highly accurate and able to operate at high speeds. Other
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has access to a controlled auxiliary power source, which depends on the engine speed. When the steering wheel is turned, a valve is opened which allows fluid under pressure to turn the driving wheels. A sensor monitors that pressure so that the valve only opens enough to cause the correct pressure to
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is a sign-sensitive delay with no delay after the ON step but with a delay after the OFF step. This is because an ON pulse immediately activates B and C, but an OFF step does not immediately result in deactivation of C because B can still be active. This can protect the system from fluctuations that
102:
Some prerequisites are needed for control scheme to be reliable by pure feed-forward without feedback: the external command or controlling signal must be available, and the effect of the output of the system on the load should be known (that usually means that the load must be predictably unchanging
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The frequent observation of feed-forward loops in various biological contexts across multiple scales suggests that they have structural properties that are highly adaptive in many contexts. Several theoretical and experimental studies including those discussed here show that FFLs create a mechanism
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Incoherent feedforward loops, in which the two paths from the input to the output node have different signs result in short pulses in response to an ON signal. In this system, input A simultaneous directly increases and indirectly decreases synthesis of output node C. If the indirect path to C (via
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Additionally, feedforward loops can facilitate cellular memory. Doncic and
Skotheim (2003) show this effect in the regulation in the mating of yeast, where extracellular mating pheromone induces mating behavior, including preventing cells from entering the cell cycle. The mating pheromone activates
177:
systems. Feedforward control requires a mathematical model of the plant (process and/or machine being controlled) and the plant's relationship to any inputs or feedback the system might receive. Neither open loop control nor teleoperator systems require the sophistication of a mathematical model of
126:
With feed-forward or feedforward control, the disturbances are measured and accounted for before they have time to affect the system. In the house example, a feed-forward system may measure the fact that the door is opened and automatically turn on the heater before the house can get too cold. The
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can be controlled via a type-1 coherent FFL. In diauxic growth cells growth using two carbon sources by first rapidly consuming the preferred carbon source, and then slowing growth in a lag phase before consuming the second less preferred carbon source. In E. coli, glucose is preferred over both
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and when it is not. The target joint angles are adjusted to place the payload in the desired position based on knowing the deflections in the arm from the mathematical model's interpretation of the disturbance caused by the payload. Systems that plan actions and then pass the plan to a different
145:
There are three types of control systems: open loop, feed-forward, and feedback. An example of a pure open loop control system is manual non-power-assisted steering of a motor car; the steering system does not have access to an auxiliary power source and does not respond to varying resistance to
1819:
Lee, Tong Ihn; Rinaldi, Nicola J.; Robert, François; Odom, Duncan T.; Bar-Joseph, Ziv; Gerber, Georg K.; Hannett, Nancy M.; Harbison, Christopher T.; Thompson, Craig M.; Simon, Itamar; Zeitlinger, Julia; Jennings, Ezra G.; Murray, Heather L.; Gordon, D. Benjamin; Ren, Bing (25 October 2002).
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control system, which has the function of keeping the body's internal environment 'steady' or in a 'prolonged steady state of readiness.' A homeostatic control system relies mainly on feedback (especially negative), in addition to the feedforward elements of the system.
1252:. This system therefore filters out fluctuations in the on-signal and detects persistent signals. This is particularly relevant in settings with stochastically fluctuating signals. In bacteria these circuits create time delays ranging from a few minutes to a few hours.
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Feedforward control requires integration of the mathematical model into the control algorithm such that it is used to determine the control actions based on what is known about the state of the system being controlled. In the case of control for a lightweight, flexible
98:
In a feed-forward system, the control variable adjustment is not error-based. Instead it is based on knowledge about the process in the form of a mathematical model of the process and knowledge about, or measurements of, the process disturbances.
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the three arrows can be either repression or activation, which can be classified into coherent or incoherent FFLs. Coherent FFLs have the same sign for both the paths from A to C, and incoherent FFLs have different signs for the two paths.
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If the driver is included in the system, then they do provide a feedback path by observing the direction of travel and compensating for errors by turning the steering wheel. In that case you have a feedback system, and the block labeled
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the MAPK pathway, which then activates the cell-cycle inhibitor Far1 and the transcription factor Ste12, which in turn increases the synthesis of inactive Far1. In this system, the concentration of active Far1 depends on the time
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Leu, M.C., Dukovski, V. and Wang, K.K., "An
Analytical and Experimental Study of the Stiffness of Robot Manipulators with Parallel Mechanisms", 1985 ASME Winter Annual Meeting PRD-Vol. 15 Robotics and Manufacturing Automation,
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Amit, Ido; Citri, Ami; Shay, Tal; Lu, Yiling; Katz, Menachem; Zhang, Fan; Tarcic, Gabi; Siwak, Doris; Lahad, John; Jacob-Hirsch, Jasmine; Amariglio, Ninette; Vaisman, Nora; Segal, Eran; Rechavi, Gideon; Alon, Uri (April 2007).
339:). Feedback regulation of the heartbeat provides further adaptiveness to the running eventualities of physical exertion. Feedforward systems are also found in biological control of other variables by many regions of animals
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or plant being controlled. Control based on operator input without integral processing and interpretation through a mathematical model of the system is a teleoperator system and is not considered feedforward control.
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of a function of the external mating pheromone concentration. This dependence on past levels of mating pheromone is a form of cellular memory. This system simultaneously allows for the stability and reversibility.
484:
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Book, W.J., Maizzo Neto, 0. and
Whitney, D.E., "Feedback Control of Two Beam, Two Joint Systems With Distributed Flexibility", Journal of Dynamic Systems, Measurement and Control, Vol.97, No.4, December 1975,
134:. The discipline of feedforward control as it relates to modern, CPU based automatic controls is widely discussed, but is seldom practiced due to the difficulty and expense of developing or providing for the
1653:
Alberts, T.E., Sangveraphunsiri, V. and Book, Wayne J., Optimal
Control of a Flexible Manipulator Arm: Volume I, Dynamic Modeling, MHRC Technical Report, MHRC-TR-85-06, Georgia Inst, of Technology, 1985.
91:
A control system which has only feed-forward behavior responds to its control signal in a pre-defined way without responding to the way the system reacts; it is in contrast with a system that also has
242:
The benefits of feedforward control are significant and can often justify the extra cost, time and effort required to implement the technology. Control accuracy can often be improved by as much as an
2344:
Meirovitch, L., "Modeling and control of
Distributed Structures" Proc. of the Workshop on Application of Distributed System Theory to Large Space Structures, JPL/CIT, NTIS #N83- 36064, July 1, 1983.
2335:
Book, W.J., "Recursive
Lagrangian Dynamics of Flexible Manipulator Arms Via Transformation Matrices", Carnegie-Mellon University Robotics Institute Technical Report, CMU-RI-TR-8323, Dec. 1983.
1641:
Oosting, K.W., Simulation of
Control Strategies for a Two Degree-of-Freedom Lightweight Flexible Robotic Arm, Thesis, Georgia Institute of Technology, Dept. of Mechanical Engineering, 1987.
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are generally writing about theories of how human or animal brains work. Black also has US patent 2102671 invented 2 August 1927 on the technique of feedback applied to electronic systems.
1674:
Alberts, T.E., Augmenting the
Control of A Flexible Manipulator with Passive Mechanical Damping, PhD. Thesis, Georgia Institute of Technology, Dept. of Mechanical Engineering, August 1986.
1573:
2365:
Hollars, M. G., Uhlik, C. R., and Cannon, R. H., "Comparison of
Decoupled and Exact Computed Torque Control for Robots with Elastic Joints", Advance copy submitted for publication, 1987.
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Nemir, D. C, Koivo, A. J., and
Kashyap, R. L., "Pseudolinks and the Self-Tuning Control of a Nonrigid Link Mechanism", Purdue University, Advance copy submitted for publication, 1987.
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that passes a controlling signal from a source in its external environment to a load elsewhere in its external environment. This is often a command signal from an external operator.
308:
uses on a feedback loop to control the operation of the system. In an open system, the output of the system is not fed back into the input to the system for control or operation.
151:
reach the wheel turning mechanism. This is feed-forward control where the output of the system, the change in direction of travel of the vehicle, plays no part in the system. See
2347:
Schmitz, E., "Experiments on the End-point Position Control of a Very Flexible One Link.Manipulator", Ph.D. Dissertation,-Stanford Univ., Dept. of Aero & Astro., June 1985.
850:
2332:
Book, W.J., "Analysis of Massless Elastic Chains With Servo Controlled Joints", Journal of Dynamic Systems, Measurement and Control, Vol.101, September 1979, pp. 187–192.
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Feed-forward loops (FFLs), a three-node graph of the form A affects B and C and B affects C, are frequently observed in transcription networks in several organisms including
1344:. The absence of glucose is represented via a small molecule cAMP. Diauxic growth in glucose and lactose is regulated by a simple regulatory system involving cAMP and the
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716:
689:
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Hastings, G.G., Controlling Flexible Manipulators, An Experimental Investigation, Ph.D. Dissertation, Dept. of Mech. Eng., Georgia Institute of Technology, August, 1986.
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595:
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Cannon, R. H. and Schmitz, E., "Initial Experiments on the End- Point Control of a Flexible One Link Robot", International Journal of Robotics Research, November 1983.
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Zalucky, A. and Hardt, D.E., "Active Control of Robot Structure Deflections", J. of Dynamic Systems, Measurement and Control, Vol. 106, March 1984, pp. 63–69.
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result in the transient loss of the ON signal and can also provide a form of memory. Kalir, Mangan, and Alon, 2005 show that the regulatory system for flagella in
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876:
907:
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Sangveraphunsiri, V., The Optimal Control and Design of a Flexible Manipulator Arm, Ph.D. Dissertation, Dept. of Mech. Eng., Georgia Inst, of Tech., 1984. 1985.
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MacKay, D. M. (1966): "Cerebral organization and the conscious control of action". In: J. C. Eccles (Ed.), Brain and conscious experience, Springer, pp. 422–440
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Meckl, P.H. and Seering, W.P., "Feedforward Control Techniques Achieve Fast Settling Time in Robots", Automatic Control Conference Proceedings. 1986, pp 58–64.
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for biological systems to process and store information, which is important for predictive behavior and survival in complex dynamically changing environments.
2338:
Hughes, P.C., "Dynamics of a Flexible Manipulator Arm for the Space Shuttle", AAS/AIAA Astrodynamics Conference, September 1977, Jackson Lake Lodge, Wyoming.
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B) is slower than the direct path a pulse of output is produced in the time period before levels of B are high enough to inhibit synthesis of C. Response to
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or it may be learned by the control system. Control systems capable of learning and/or adapting their mathematical model have become more practical as
251:
benefits of feedforward control include reduced wear and tear on equipment, lower maintenance costs, higher reliability and a substantial reduction in
1713:
2362:
Widmann, G. R. and Ahmad, S., "Control of Industrial Robots with Flexible Joints", Purdue University, Advance copy submitted for publication, 1987.
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as early as 1956. While MacKay's work is in the field of biological control theory, he speaks only of feedforward systems. MacKay does not mention
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Sakawa, Y., Matsuno, F. and Fukushima, S., "Modeling and Feedback Control of a Flexible Arm", Journal of Robotic Systems. August 1985, pp 453–472.
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490:
331:, feed-forward control is exemplified by the normal anticipatory regulation of heartbeat in advance of actual physical exertion by the central
2300:
Book, W.J. and Cetinkunt, S., "Optimum Control of Flexible Robot Arms OR Fixed Paths", IEEE Conference on Decision and Control. December 1985.
1791:
Greene, P. H. (1969): "Seeking mathematical models of skilled actions". In: H. C. Muffley/D. Bootzin (Eds.), Biomechanics, Plenum, pp. 149–180
2316:
Asada, H., Youcef-Toumi, K. and Ramirez, R.B., "Designing of the MIT Direct Drive Arm", Int. Symp. on Design and Synthesis, Japan, July 1984.
414:
2286:
S. Mangan A. Zaslaver & U. Alon, "The coherent feed-forward loop serves as a sign-sensitive delay element in transcription networks",
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transcription networks have been extensively studied, FFLs occur approximately three times more frequently than expected based on random (
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The mathematical model of the plant (machine, process or organism) used by the feedforward control system may be created and input by a
405:
The temporal dynamics of FFLs show that coherent FFLs can be sign-sensitive delays that filter input into the circuit. We consider the
2377:
Oosting, K.W. and Dickerson, S.L., "Control of a Lightweight Robot Arm", 1986, IEEE International Conference on Industrial Automation
322:
2322:
Balas, M.J., "Feedback Control of Flexible Systems", IEEE Trans. on Automatic Control, Vol.AC-23, No.4, Aug. 1978, pp. 673–679.
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of the plant (body) can be considered to be mathematical as the model is characterized by limits, rhythms, mechanics and patterns.
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Hughes, P.C., "Dynamics of a Chain of Flexible Bodies", Journal of Astronautical Sciences, 27,4, Oct.-Dec. 1979, pp. 359–380.
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speeds have increased. The discipline of modern feedforward control was itself made possible by the invention of microprocessors.
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1809:
Maizza-Neto, 0., Modal Analysis and Control of Flexible Manipulator Arms, PhD. Thesis-, MIT, Dept. of Mech. Eng., September 1974.
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if the mathematical model is of sufficient quality and implementation of the feedforward control law is well thought out.
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turning of the direction wheels; the driver must make that response without help from the steering system. In comparison,
95:, which adjusts the input to take account of how it affects the system, and how the system itself may vary unpredictably.
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2350:
Martin, G.D., On the Control of Flexible Mechanical Systems, Ph.D. Dissertation, Stanford Univ., Dept. of E.E., May 1978.
1800:
Book, W.J., Modeling, Design and Control of Flexible Manipulator Arms, PhD. Thesis, MIT, Dept. of Mech. Eng., April 1974.
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2457:
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Truckenbrodt, A., "Modeling and Control of Flexible Manipulator Structures", 4th CISM-IFToMM Symp., Warszawa, 1981.
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1403:. The connections are set up during a training phase, which in effect is when the system is a feedback system.
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Rameriz, R.B., Design of a High Speed Graphite Composite Robot Arm, M.S. Thesis, M.E. Dept., MIT, Feb. 1984.
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required to facilitate this type of control. Open-loop control and feedback control, often based on canned
2405:
2045:"A coherent feed-forward loop with a SUM input function prolongs flagella expression in Escherichia coli"
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391:
382:, suggesting that they perform functions that are important for the functioning of these organisms. In
231:
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Balas, M.J., "Active Control of Flexible Systems", J. of Optim. Th. and App., Vol.25, No.3, July 1978,
1415:, used feed-forward amplifiers to diminish linear distortion. This more complex method allowed wider
2462:
2371:
Oosting, K.W. and Dickerson, S.L., "Low-Cost, High Speed Automated Inspection", 1991, Industry Report
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Oosting, K.W. and Dickerson, S.L., "Low-Cost, High Speed Automated Inspection", 1991, Industry Report
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Book, W.J.; Cetinkunt, S. (December 1985). "Optimum Control of Flexible Robot Arms OR Fixed Paths".
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The method is rather a new technique that changes the phase of an open-loop transfer function of a
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2102:"The coherent feedforward loop serves as a sign-sensitive delay element in transcription networks"
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Milo, R.; Shen-Orr, S.; Itzkovitz, S.; Kashtan, N.; Chklovskii, D.; Alon, U. (25 October 2002).
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and then applies an additional input to minimize the effect of the disturbance. This requires a
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Feedforward control is a discipline within the field of automatic controls used in automation.
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In other words, systems of different types can be nested, and the overall system regarded as a
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Oosting, K.W., "Actuated Feedforward Controlled Solar Tracking System", 2009, Patent Pending
1090:. In this case the FFL creates a time-delay between a sustained on-signal, i.e. increase in
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1962:
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1025:{\displaystyle \beta _{C}(A,B)=\beta _{C}\theta _{A}(A>k_{AC})\theta _{A}(B>k_{ABC})}
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335:. Feed-forward control can be likened to learned anticipatory responses to known cues (
255:. Feedforward control is often combined with feedback control to optimize performance.
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Oosting, K.W. and Dickerson, S.L., "Feed Forward Control for Stabilization", 1987, ASME
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Oosting, K.W. and Dickerson, S.L., "Feed Forward Control for Stabilization", 1987, ASME
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is found in works by Harold S. Black in US patent 1686792 (invented 17 March 1923) and
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2149:"Feedforward Regulation Ensures Stability and Rapid Reversibility of a Cellular State"
1993:
1950:
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Oosting, K.W., "Feedforward Control System for a Solar Tracker", 2009, Patent Pending
2262:"Tip Position Control of Single Flexible Links via Parallel Feedforward Compensation"
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279:, this could be as simple as compensating between when the robot arm is carrying a
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For instance, the regulation of the shift from one carbon source to another in
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1190:. However, there is no time-delay in for an off-signal because a reduction of
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Oosting, K.W., "Smart Solar Tracking", July, 2010, InterSolar NA Presentation
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1984:
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Oosting, K.W.; Dickerson, S.L. (1986). "Control of a Lightweight Robot Arm".
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Control paradigm in which errors are measured before they can affect a system
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An Introduction to Systems Biology: Design Principles of Biological Circuits
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of the system so that the effect of disturbances can be properly predicted.
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2207:"A module of negative feedback regulators defines growth factor signaling"
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561:{\displaystyle {\frac {\delta C}{\delta t}}=\beta _{C}(A,B)-\gamma _{C}C}
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479:{\displaystyle {\frac {\delta B}{\delta t}}=\beta _{B}(A)-\gamma _{B}B}
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Feedforward control is distinctly different from open loop control and
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In the early 1970s, intercity coaxial transmission systems, including
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in dividing mammalian cells is an example of a Type-1 incoherent FFL.
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Even in the case of biological feedforward systems, such as in the
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1822:"Transcriptional Regulatory Networks in Saccharomyces cerevisiae"
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2446:
1951:"Structure and function of the feed-forward loop network motif"
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81:
77:
1427:, however, made such systems obsolete before many were built.
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for a Type-I coherent FFL, where all the arrows are positive:
340:
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was largely developed by professors and graduate students at
2043:
Kalir, Shiraz; Mangan, Shmoolik; Alon, Uri (29 March 2005).
1885:"Network Motifs: Simple Building Blocks of Complex Networks"
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The term has specific meaning within the field of CPU-based
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are rate constants representing degradation or dilution of
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Parallel feed-forward compensation with derivative (PFCD)
1210:
immediately results in a decrease in the production term
2100:
Mangan, S.; Zaslaver, A.; Alon, U. (21 November 2003).
1604:
1764:"Learned Feed Forward - Innovations in Motion Control"
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IEEE International Conference on Industrial Automation
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is regulated with a Type 1 coherent feedforward loop.
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1766:. Technology Association of Georgia. Archived from
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2147:Doncic, Andreas; Skotheim, Jan M. (27 June 2013).
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207:. MacKay and other early writers who use the term
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300:is a feed forward system that does not have any
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1955:Proceedings of the National Academy of Sciences
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357:A pure feed-forward system is different from a
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2293:Foss, S., Foss, K., & Trapp. (2002).
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1949:Mangan, S.; Alon, U. (14 October 2003).
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1496:"A Dictionary of Mechanical Engineering"
27:
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1719:. Ben Gurion University. Archived from
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1607:IEEE Conference on Decision and Control
1494:Escudier, Marcel; Atkins, Tony (2019).
163:in Figure(c) is a feed-forward system.
142:algorithms, are much more widely used.
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1391:network in which the outputs from all
304:to control its output. In contrast, a
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2295:Contemporary Perspectives on Rhetoric
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1944:
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323:Neural top–down control of physiology
80:to detect disturbances affecting the
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2015:
1504:10.1093/acref/9780198832102.001.0001
1387:, feed-forward normally refers to a
61:) is an element or pathway within a
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13:
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1939:
1395:go to following but not preceding
191:Historically, the use of the term
14:
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1373:Feed-forward systems in computing
845:{\displaystyle \beta _{C}(A,B)=0}
317:Physiological feed-forward system
32:The three types of control system
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2707:
2706:
1574:"Fundamentals of Motion Control"
1150:must first induce production of
1130:. This is because production of
366:Gene regulation and feed-forward
2463:Central pattern generator (CPG)
2297:(3rd ed.). Waveland Press, Inc.
2253:
2197:
2140:
2093:
2036:
2009:
1876:
1812:
1756:
1706:
1245:{\displaystyle \beta _{C}(A,B)}
793:{\displaystyle \beta _{C}(A,B)}
311:
203:or allude to the discipline of
2657:Frog hearing and communication
1613:
1598:
1541:
1487:
1478:
1431:Automation and machine control
1239:
1227:
1019:
994:
981:
959:
933:
921:
833:
821:
787:
775:
539:
527:
457:
451:
287:
106:These systems could relate to
76:is a control system that uses
45:Feedback (closed loop) control
1:
1701:Springer Handbook of Robotics
1471:
1363:epidermal growth factor (EGF)
664:representing production, and
2165:10.1016/j.molcel.2013.04.014
2106:Journal of Molecular Biology
1909:10.1126/science.298.5594.824
624:are increasing functions in
7:
1454:
1110:and the output increase in
1079:{\displaystyle \theta _{B}}
1052:{\displaystyle \theta _{A}}
711:{\displaystyle \gamma _{z}}
684:{\displaystyle \gamma _{Y}}
237:
121:
10:
2778:
2752:Artificial neural networks
2662:Infrared sensing in snakes
2647:Jamming avoidance response
1550:Basic Dynamics and Control
1376:
617:{\displaystyle \beta _{z}}
590:{\displaystyle \beta _{y}}
320:
186:
74:feedforward control system
18:
2702:
2629:
2608:
2512:
2428:
2118:10.1016/j.jmb.2003.09.049
2049:Molecular Systems Biology
2016:Alon, Uri (7 July 2006).
2667:Caridoid escape reaction
1703:, Springer-Verlag, 2008.
258:
153:Model predictive control
2520:Theodore Holmes Bullock
1976:10.1073/pnas.2133841100
1846:10.1126/science.1075090
1484:Based on Hopgood (2002)
1407:Long distance telephony
1279:is activated by either
2757:Neuroethology concepts
2677:Surface wave detection
1529:Cite journal requires
1313:
1293:
1273:
1246:
1204:
1184:
1164:
1144:
1124:
1104:
1080:
1053:
1026:
898:
872:
846:
794:
752:
732:
712:
685:
658:
638:
618:
591:
562:
480:
407:differential equations
399:transcription networks
50:
2493:Anti-Hebbian learning
1714:"Feedforward control"
1579:. ISA. Archived from
1314:
1294:
1274:
1247:
1205:
1185:
1165:
1145:
1125:
1105:
1081:
1054:
1027:
899:
873:
847:
795:
753:
733:
713:
686:
659:
639:
619:
592:
563:
481:
31:
2570:Bernhard Hassenstein
2503:Ultrasound avoidance
2478:Fixed action pattern
2441:Coincidence detector
2288:J. Molecular Biology
1695:Bruno Siciliano and
1586:on 27 September 2011
1303:
1283:
1263:
1214:
1194:
1174:
1154:
1134:
1114:
1094:
1063:
1036:
908:
882:
856:
808:
762:
742:
722:
695:
668:
648:
628:
601:
574:
491:
415:
216:feedforward controls
205:feedforward controls
19:For other uses, see
2637:Animal echolocation
2575:Werner E. Reichardt
2525:Walter Heiligenberg
2290:334:197-204 (2003).
1967:2003PNAS..10011980M
1961:(21): 11980–11985.
1901:2002Sci...298..824M
1838:2002Sci...298..799L
1726:on 27 November 2020
1548:Haugen, F. (2009).
897:{\displaystyle B=0}
871:{\displaystyle A=0}
201:feedforward control
70:control engineering
57:(sometimes written
2600:Fernando Nottebohm
2498:Sound localization
2473:Lateral inhibition
2260:Noury, K. (2019).
2061:10.1038/msb4100010
1399:, so there are no
1309:
1289:
1269:
1242:
1200:
1180:
1160:
1140:
1120:
1100:
1076:
1049:
1022:
904:, for instance if
894:
868:
842:
790:
748:
728:
708:
681:
654:
634:
614:
587:
558:
476:
248:Energy consumption
244:order of magnitude
214:The discipline of
136:mathematical model
86:mathematical model
51:
2734:
2733:
2621:Slice preparation
2483:Krogh's Principle
2458:Feature detection
2329:pp. 424–430.
2029:978-1-58488-642-6
1895:(5594): 824–827.
1832:(5594): 799–804.
1559:978-82-91748-13-9
1513:978-0-19-883210-2
1445:non-minimum phase
1312:{\displaystyle B}
1292:{\displaystyle A}
1272:{\displaystyle C}
1257:inclusive-OR gate
1203:{\displaystyle A}
1183:{\displaystyle C}
1163:{\displaystyle B}
1143:{\displaystyle A}
1123:{\displaystyle C}
1103:{\displaystyle A}
800:can represent an
751:{\displaystyle C}
731:{\displaystyle B}
657:{\displaystyle B}
637:{\displaystyle A}
512:
436:
350:, knowledge or a
337:predictive coding
333:autonomic network
132:automatic control
37:Open-loop control
2769:
2722:
2721:
2710:
2709:
2687:Mechanoreception
2682:Electroreception
2595:Masakazu Konishi
2560:Jörg-Peter Ewert
2415:
2408:
2401:
2392:
2391:
2313:pp. 137–144
2273:
2272:
2266:
2257:
2251:
2250:
2201:
2195:
2194:
2184:
2144:
2138:
2137:
2097:
2091:
2090:
2080:
2040:
2034:
2033:
2013:
2007:
2006:
1996:
1978:
1946:
1937:
1936:
1880:
1874:
1873:
1816:
1810:
1807:
1801:
1798:
1792:
1789:
1780:
1779:
1777:
1775:
1770:on 16 March 2012
1760:
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1626:
1625:
1617:
1611:
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1602:
1596:
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1593:
1591:
1585:
1578:
1570:
1564:
1563:
1545:
1539:
1538:
1532:
1527:
1525:
1517:
1491:
1485:
1482:
1318:
1316:
1315:
1310:
1298:
1296:
1295:
1290:
1278:
1276:
1275:
1270:
1251:
1249:
1248:
1243:
1226:
1225:
1209:
1207:
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1201:
1189:
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1129:
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1085:
1083:
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1077:
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1055:
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1031:
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1023:
1018:
1017:
993:
992:
980:
979:
958:
957:
948:
947:
920:
919:
903:
901:
900:
895:
877:
875:
874:
869:
851:
849:
848:
843:
820:
819:
799:
797:
796:
791:
774:
773:
757:
755:
754:
749:
737:
735:
734:
729:
717:
715:
714:
709:
707:
706:
690:
688:
687:
682:
680:
679:
663:
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612:
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586:
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567:
565:
564:
559:
554:
553:
526:
525:
513:
511:
503:
495:
485:
483:
482:
477:
472:
471:
450:
449:
437:
435:
427:
419:
265:control engineer
2777:
2776:
2772:
2771:
2770:
2768:
2767:
2766:
2737:
2736:
2735:
2730:
2698:
2652:Vision in toads
2625:
2604:
2555:Erich von Holst
2550:Karl von Frisch
2508:
2424:
2419:
2389:
2282:
2280:Further reading
2277:
2276:
2264:
2258:
2254:
2211:Nature Genetics
2202:
2198:
2145:
2141:
2098:
2094:
2041:
2037:
2030:
2014:
2010:
1947:
1940:
1881:
1877:
1817:
1813:
1808:
1804:
1799:
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1790:
1783:
1773:
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1762:
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1743:
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1729:
1727:
1723:
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1712:
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1707:
1694:
1690:
1685:
1678:
1673:
1669:
1664:
1657:
1652:
1645:
1640:
1629:
1618:
1614:
1603:
1599:
1589:
1587:
1583:
1576:
1572:
1571:
1567:
1560:
1546:
1542:
1530:
1528:
1519:
1518:
1514:
1492:
1488:
1483:
1479:
1474:
1466:Smith predictor
1457:
1441:
1433:
1409:
1381:
1375:
1304:
1301:
1300:
1284:
1281:
1280:
1264:
1261:
1260:
1221:
1217:
1215:
1212:
1211:
1195:
1192:
1191:
1175:
1172:
1171:
1155:
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1151:
1135:
1132:
1131:
1115:
1112:
1111:
1095:
1092:
1091:
1070:
1066:
1064:
1061:
1060:
1043:
1039:
1037:
1034:
1033:
1007:
1003:
988:
984:
972:
968:
953:
949:
943:
939:
915:
911:
909:
906:
905:
883:
880:
879:
857:
854:
853:
815:
811:
809:
806:
805:
769:
765:
763:
760:
759:
743:
740:
739:
723:
720:
719:
702:
698:
696:
693:
692:
675:
671:
669:
666:
665:
649:
646:
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629:
626:
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608:
604:
602:
599:
598:
581:
577:
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572:
571:
549:
545:
521:
517:
504:
496:
494:
492:
489:
488:
467:
463:
445:
441:
428:
420:
418:
416:
413:
412:
368:
325:
319:
314:
290:
261:
240:
232:Carnegie Mellon
189:
180:physical system
124:
49:
24:
17:
12:
11:
5:
2775:
2765:
2764:
2759:
2754:
2749:
2747:Control theory
2732:
2731:
2729:
2728:
2716:
2703:
2700:
2699:
2697:
2696:
2695:
2694:
2684:
2679:
2674:
2672:Vocal learning
2669:
2664:
2659:
2654:
2649:
2644:
2639:
2633:
2631:
2627:
2626:
2624:
2623:
2618:
2612:
2610:
2606:
2605:
2603:
2602:
2597:
2592:
2587:
2582:
2577:
2572:
2567:
2562:
2557:
2552:
2547:
2545:Donald Kennedy
2542:
2540:Donald Griffin
2537:
2532:
2530:Niko Tinbergen
2527:
2522:
2516:
2514:
2510:
2509:
2507:
2506:
2500:
2495:
2490:
2488:Hebbian theory
2485:
2480:
2475:
2470:
2465:
2460:
2455:
2450:
2443:
2438:
2432:
2430:
2426:
2425:
2418:
2417:
2410:
2403:
2395:
2388:
2387:
2384:
2381:
2378:
2375:
2372:
2369:
2366:
2363:
2360:
2357:
2354:
2351:
2348:
2345:
2342:
2339:
2336:
2333:
2330:
2326:
2323:
2320:
2317:
2314:
2310:
2307:
2304:
2301:
2298:
2291:
2283:
2281:
2278:
2275:
2274:
2252:
2223:10.1038/ng1987
2217:(4): 503–512.
2196:
2159:(6): 856–868.
2153:Molecular Cell
2139:
2112:(2): 197–204.
2092:
2035:
2028:
2008:
1938:
1875:
1811:
1802:
1793:
1781:
1755:
1746:
1737:
1705:
1697:Oussama Khatib
1688:
1676:
1667:
1655:
1643:
1627:
1612:
1597:
1565:
1558:
1540:
1531:|journal=
1512:
1486:
1476:
1475:
1473:
1470:
1469:
1468:
1463:
1456:
1453:
1440:
1437:
1432:
1429:
1408:
1405:
1401:feedback loops
1377:Main article:
1374:
1371:
1329:diauxic growth
1308:
1288:
1268:
1255:Similarly, an
1241:
1238:
1235:
1232:
1229:
1224:
1220:
1199:
1179:
1159:
1139:
1119:
1099:
1088:step functions
1073:
1069:
1046:
1042:
1021:
1016:
1013:
1010:
1006:
1002:
999:
996:
991:
987:
983:
978:
975:
971:
967:
964:
961:
956:
952:
946:
942:
938:
935:
932:
929:
926:
923:
918:
914:
893:
890:
887:
867:
864:
861:
841:
838:
835:
832:
829:
826:
823:
818:
814:
789:
786:
783:
780:
777:
772:
768:
758:respectively.
747:
727:
705:
701:
678:
674:
653:
633:
611:
607:
584:
580:
557:
552:
548:
544:
541:
538:
535:
532:
529:
524:
520:
516:
510:
507:
502:
499:
475:
470:
466:
462:
459:
456:
453:
448:
444:
440:
434:
431:
426:
423:
367:
364:
321:Main article:
318:
315:
313:
310:
294:systems theory
289:
286:
269:microprocessor
260:
257:
239:
236:
188:
185:
148:power steering
123:
120:
108:control theory
63:control system
48:
47:
42:
39:
33:
15:
9:
6:
4:
3:
2:
2774:
2763:
2760:
2758:
2755:
2753:
2750:
2748:
2745:
2744:
2742:
2727:
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2717:
2715:
2714:
2705:
2704:
2701:
2693:
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2673:
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2668:
2665:
2663:
2660:
2658:
2655:
2653:
2650:
2648:
2645:
2643:
2640:
2638:
2635:
2634:
2632:
2628:
2622:
2619:
2617:
2614:
2613:
2611:
2607:
2601:
2598:
2596:
2593:
2591:
2588:
2586:
2583:
2581:
2578:
2576:
2573:
2571:
2568:
2566:
2563:
2561:
2558:
2556:
2553:
2551:
2548:
2546:
2543:
2541:
2538:
2536:
2535:Konrad Lorenz
2533:
2531:
2528:
2526:
2523:
2521:
2518:
2517:
2515:
2511:
2504:
2501:
2499:
2496:
2494:
2491:
2489:
2486:
2484:
2481:
2479:
2476:
2474:
2471:
2469:
2468:NMDA receptor
2466:
2464:
2461:
2459:
2456:
2454:
2451:
2449:
2448:
2444:
2442:
2439:
2437:
2434:
2433:
2431:
2427:
2423:
2422:Neuroethology
2416:
2411:
2409:
2404:
2402:
2397:
2396:
2393:
2385:
2382:
2379:
2376:
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2367:
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2358:
2355:
2352:
2349:
2346:
2343:
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2331:
2327:
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2318:
2315:
2311:
2308:
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2299:
2296:
2292:
2289:
2285:
2284:
2270:
2263:
2256:
2248:
2244:
2240:
2236:
2232:
2228:
2224:
2220:
2216:
2212:
2208:
2200:
2192:
2188:
2183:
2178:
2174:
2170:
2166:
2162:
2158:
2154:
2150:
2143:
2135:
2131:
2127:
2123:
2119:
2115:
2111:
2107:
2103:
2096:
2088:
2084:
2079:
2074:
2070:
2066:
2062:
2058:
2055:: 2005.0006.
2054:
2050:
2046:
2039:
2031:
2025:
2022:. CRC Press.
2021:
2020:
2012:
2004:
2000:
1995:
1990:
1986:
1982:
1977:
1972:
1968:
1964:
1960:
1956:
1952:
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1943:
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1930:
1926:
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1555:
1551:
1544:
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1523:
1515:
1509:
1505:
1501:
1497:
1490:
1481:
1477:
1467:
1464:
1462:
1459:
1458:
1452:
1450:
1449:minimum phase
1446:
1436:
1428:
1426:
1425:Optical fiber
1422:
1419:than earlier
1418:
1414:
1404:
1402:
1398:
1394:
1390:
1386:
1380:
1370:
1366:
1364:
1358:
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1323:
1306:
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1233:
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1222:
1218:
1197:
1177:
1157:
1137:
1117:
1097:
1089:
1071:
1067:
1044:
1040:
1014:
1011:
1008:
1004:
1000:
997:
989:
985:
976:
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969:
965:
962:
954:
950:
944:
940:
936:
930:
927:
924:
916:
912:
891:
888:
885:
865:
862:
859:
839:
836:
830:
827:
824:
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803:
784:
781:
778:
770:
766:
745:
725:
703:
699:
676:
672:
651:
631:
609:
605:
582:
578:
568:
555:
550:
546:
542:
536:
533:
530:
522:
518:
514:
508:
505:
500:
497:
486:
473:
468:
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2616:Patch clamp
2585:Eric Kandel
2565:Franz Huber
2436:Feedforward
1774:24 February
1730:23 February
1590:23 February
392:Erdös-Rényi
359:homeostatic
348:human brain
298:open system
288:Open system
277:robotic arm
209:feedforward
193:feedforward
140:PID control
59:feedforward
21:Feedforward
2762:Automation
2741:Categories
2590:Nobuo Suga
2505:in insects
1472:References
1423:systems.
1389:perceptron
1379:Perceptron
1346:lac operon
852:if either
329:physiology
253:hysteresis
112:physiology
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2173:1097-2765
2126:0022-2836
2069:1744-4292
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2003:14530388
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